Collect the Cards

Each book contains six cards strapped to the inside cover. But don’t worry, you can collect more cards by purchasing the four card packs, which will be released with the first, fourth, seventh and ninth book in the series. Each card pack contains 16 cards chosen at random. So buy the packs, and collect the set!

Play the Game

Log onto the39clues.com to create an account and begin your adventure. You can start your own online card collection, find out which branch of the Cahill family you’re best suited to (Janus, Lucian, Ekaterina or Tomas), and begin your hunt for the 39 clues!